A male-male termite pair makes nests, just as heterosexual termite couples do. Male Japanese termites form homosexual couples when no females are around -- and when the chance arises, they take over a heterosexual couple's nest and kill the male so that one of them can mate with the now spouseless female. The study supports a theory that homosexual couplings in invertebrates have evolutionary advantages. CREDIT Nobuaki Mizumoto

Male Japanese termites form homosexual couples when no females are around — and when the chance arises, they take over a heterosexual couple’s nest and kill the male so that one of them can mate with the now spouseless female, scientists from Kyoto University reported in a study published this week in the research journal Animal Behaviour. The evolutionary paradox of homosexuality has long puzzled biologists, the university said in a statement entitled Homosexual Termite Regicide. “The observations support a theory that homosexual couplings in invertebrates have evolutionary advantages.”

The statement continued: “Recent research suggests that there are benefits associated with homosexuality, at least for mammals and birds. As for invertebrates like insects, experts have considered that homosexual behavior results from an inopportune misrecognition of males as females. But lead scientist Nobuaki Mizumoto and colleagues discovered that male termites aren’t so inobservant; they behaved differently toward males and females, and when coupling with males, they didn’t act as though they were mistaking them for females.”

“There had to be some sort of benefit if this were a common behavior”

Mizumoto explained: “Japanese termites usually make nests in monogamous, heterosexual pairs. In theory, misrecognizing a female for a male in a monogamous mating system should incur considerable costs for reproduction. There had to be some sort of benefit if this were a common behavior.”

The researchers observed that homosexual male termites built nests together, just as with heterosexual couples. “Male termites aren’t able to survive on their own, but those that make nests with another male survived for much longer,” Mizumoto said. “This was especially beneficial in situations when searching for females raises the risk of being preyed upon. It’s clear that male-male pairing is a strategy for survival.”

The team found that once workers from the heterosexual couple’s colony began digging tunnels to patrol, a male-male pair would travel back through the tunnel to invade and attempt to kill the heterosexual couple’s nest, the news release said. “From genetic analyses of subsequent offspring, the scientists found that only one of the invading males had been able to mate with the female.”

“Pairing with another male isn’t the best option, but it gives mateless termites a chance to survive until they find a female, if that happens at all,” Mizutani said. “To understand this behavior further, it will be important to consider the effects of other factors such as predators.”

This post was based on a University of Kyoto news release.

David Braun is director of outreach with the digital and social media team illuminating the National Geographic Society’s explorer, science, and education programs.

He edits National Geographic Voices, hosting a global discussion on issues resonating with the Society’s mission and major initiatives. Contributors include grantees and Society partners, as well as universities, foundations, interest groups, and individuals dedicated to a sustainable world. More than 50,000 readers have participated in 10,000 conversations.

Post a comment

National Geographic Voices

Researchers, conservationists, and others share stories, insights and ideas about our living planet's rapidly changing geography. More than 50,000 comments have been added to 10,000 posts. Explore the list alongside to dive deeper into some of the most popular categories of the National Geographic Society's conversation platform Voices.

Opinions are those of the blogger and/or the blogger's organization, and not necessarily those of the National Geographic Society. Posters and commenters are required to observe National Geographic's community rules and other terms of service.

Voices director: David Braun (dbraun@ngs.org)

Fighting Wildlife Crime: The Unsung Heroes

Journalist and National Geographic Fellow Bryan Christy uses investigative journalism to expose illegal wildlife trafficking around the globe. In this video he introduces a a series of interviews with the people fighting wildlife crime on the front lines.

Blog Search

Search for:

Fulbright-National Geographic

The Fulbright-National Geographic Digital Storytelling Fellowship provides a unique platform for U.S. Fulbright awardees to build awareness of transnational challenges, comparing and contrasting cross-border issues. Their stories are shared on National Geographic digital platforms using a variety of digital storytelling tools, including text, photography, video, audio, graphic illustrations and/or social media. Meet the Fellows and follow their adventures across the world on the Fulbright-National Geographic Storytelling blog.

Follow the links on the sidebar of any of the blog's pages for details and tips on how to apply for a Fellowship.

Photo of the 2016/2017 class of Fellows by Randall Scott.

Featured Research: Mushara Elephant Project

Caitlin O'Connell and her husband, Tim Rodwell, started the Mushara Elephant Project in Namibia 24 years ago to better understand elephant social structure, communication and health in order to apply this knowledge to improved care in captivity and ultimately to elephant conservation in the wild. O’Connell is on the faculty at Stanford University School of Medicine and CEO of the elephant-focused nonprofit, Utopia Scientific. A grantee of the National Geographic Society, she is also an award-winning author of six books about elephants. Read Caitlin's dispatches from Mushara.

Nat Geo Expedition: Rising Star

Two years after being discovered deep in a South African cave, the 1,500 fossils excavated during the Rising Star Expedition have been identified as belonging to a previously unknown early human relative that National Geographic Explorer-in-Residence Lee Berger and team have named Homo naledi.

With at least 15 individuals of all ages and both sexes represented, the find adds an unprecedented amount of information to our understanding of early human evolution in Africa.

In addition, the absence of any other animal remains or large debris in the fossil chamber strongly suggests that these non-human beings intentionally deposited their dead within this cave.